1. Field of the Invention
The invention is related to the art of toothbrushes.
2. Description of Related Art
The invention relates more particularly to electrically driven toothbrushes in which brush bristles are arranged to be moved relative to the toothbrush handle. There are many examples of such toothbrushes including the disclosure in 1939 of rotary driven bristles in U.S. Pat. No. 2,215,031, A similar rotational drive arrangement is also shown in U.S. Pat. No. 4,845,795, U.S. Pat. No. 4,156,620 explains how a rotational motor drive is converted into reciprocal linear motion to drive the bristles rotationally clockwise and counterclockwise, U.S. Pat. No. 3,577,579 discloses a toothbrush in which a toothbrush head is moved in relation to a brush holder so that all the bristles mounted in the brush head move together sideways and backwards and forwards relative to the holder. U.S. Pat. No. 5,625,916, the substance of which is hereby incorporated by reference, discloses a toothbrush with a single bristle holder. The bristle holder is driven to vibrate in a rotational manner about a shaft.
The drive mechanisms and brush motions disclosed in these references range from the relatively simple to the relatively complex. The most complex of the disclosed toothbrushes is used to provide an elaborate brushing motion. While the provided brushing motion is beneficial, the means disclosed for providing it is far too complicated and involves far too many moving parts, to be a practical brushing solution in many applications. The simpler of the disclosed toothbrushes, provide only one brushing action. While practical to produce, these single brushing actions may be inadequate in some brushing applications. For example, they may not adequately clean spaces between teeth.
It is desirable therefore, to provide a toothbrush that is simple to manufacture, and has few moving parts, while providing a plurality of cleaning or brushing actions for accomplishing a plurality of teeth cleaning tasks.
One embodiment of the new toothbrush includes a handle at a first end of the toothbrush, a head at a second end of the toothbrush, a rotatable shaft extending from the handle to the head and having a first longitudinal central axis, a first bristle holder pivotally mounted to the head and associated with a remote end of the shaft, the remote end of the shaft being received in a slot of the first bristle holder for driving the first bristle holder in pivoting vibratory movement, and a second bristle holder movably mounted to the head section and drivingly engaged by a cam located on the shaft.
Another embodiment of the electric toothbrush includes a shaft. The shaft includes a first cam and a second cam. A motor operative to rotate the shaft is also included in the toothbrush. A first brush section is operatively coupled to the first cam for a first motion. A second brush section longitudinally separated from the first brush section and separately associated with the second cam to drive the second brush section in a second motion. The second motion being distinct from the first motion.
A third embodiment of the electric toothbrush includes a shaft. The shaft includes a cam. A motor is operative to rotate the shaft. A first brush section is operatively coupled to the cam for a first motion. A second brush section is longitudinally separated from the first brush section and separately operatively coupled to the cam for a second motion. The second motion is distinct from the first motion.
For example, the second brush section can include a pivot portion located in a body of the second brush section and disposed transversely to a longitudinal axis of the second brush section, the pivot portion being operative to pivotably connect the second brush section to a head portion of the toothbrush. The second brush section includes a cam contact surface on a bottom surface thereof. The cam contact surface is operative to ride on a surface of the cam, thereby causing the second brush section to rock about the pivot portion.
One advantage of the present invention resides in distinct and complementary cleaning motions provided respectively by the first and second bristle holders
Another advantage of the present invention is that distinct and complementary cleaning motions are provided in a simple and economical toothbrush.
Still other advantages of the present invention will become apparent to those skilled in the art upon a reading and understanding of the detail description below.